Open chain active methylene color couplers



Patented Apr. 6, 1948 OPEN CHAIN ACTIVE METHYLENECOLOR COUPLERS ArnoldWeissberger and H ter, N. Y., assignors to Eastman Kodak Company,Rochester, N. Y., a corporation of New Jersey enryl). Porter, Roches- INo Drawing. ApplicationMarchZl, 1946; Serial No. 656,149

,' 12 Claims. (Cl. 95-6) This invention relates to photography andparticularly to compounds which form dyes by coupling with thedeveloping agent to produce colored images.

It is known that colored photographic images may be formed by using adeveloper which :produces a colored compound on development. The coloredcompound thus formed is deposited adjacent the silver grains of thesilver image during the developing. colored image may be formed byadding to :certain developer solutions or by incorporating in. thesilver halide emulsion .before or after exposure a compound whichcouples during development with the oxidation product of the developingagent and forms a colored compoundwhich is likewise deposited adjacentthe silver grains of,

the silver image during development. Sucha compound which is employed inconjunction with a developing agent for the silver and which coupleswith the oxidation product :of the developing agent during developmentis referred 'to herein as a coupling compoundor coupler.

The present invention concerns new or 1111- proved color-formingdevelopers comprising primary aromatic amino developing agent and acoupler as hereinafter defined and also includes a new or improved colordevelopment process which consists in developing a reducible silver saltimage in a photographic element with theaid of a primary aromaticaminodeveloper and in the presence of a coupler ashereinafter defined. It

lso includes photographic sensitive elements 5 aving such coupler in oneor more emulsion ayers.

We have found that compounds of the following structure are valuablecouplers for color photography and produce yellow to red images of highstability on development.

R-COCHzCONHCO-R ing solution or they may be of such size as to permitthe use of these compounds in theemulsion layer of multi-layerphotographic coatings.

In "the formula above, the substituent R may be an aryl radicalsuch asphenyl or naphthyl or It is also known that a 1 oflrisooomooNfloootmN-(benzoylacetyDbenzamide (2) CaHaCOCHzCONHCOCHaN-(bcnzoylacetyl)acetamide 4 -o o-oHz'ooNHo 0 com'N-(fi-naphthbylacetyl)-benzamide N-acety1-a-(4,5-benzoiuroyl)-acetamideThese compounds contain a coupling function which in thiscase is areactive methylenegroup. By couplingfunction we mean a functionalorreactive group common tocoupler compounds which react with thedevelopment product of a primary aromatic-aminodeveloping agent. By

reactive methylene we mean a methylene group which is reactive in thecoupling process, in this casethe group present between twonegativecenters as in the group -CO-CHzCO--.

The aromatic amino developing agents usedphenylenediamine-hydrochloride, dimethyl pphenylenediamine-hydrochloride and dimethylp-phenylenediamine sulphate.Developing agents containing heterocyclic systems as described in U. S.Patent 2,196,739 are also suitable. The paminophenols and theirsubstitution products may also be used where the amino group is unsubstituted. All of these compounds have an unsubstituted amino groupwhich enables the.

oxidation products of the developer to couple with the color-formingcompounds to form a dye image.

The compounds of our invention may be prepared according to thefollowing general reactions:

R'COCl RCOCHzC -v RCOOHQC Pyridine NCOR I II

-- RCO oHiooNHc on No OR I RGOCHQC III where R and R have the samemeanings as stated above.

The starting imidoesters (l) were prepared from the reaction of ethanoland hydrogen chloride on the corresponding nitriles. The condensation ofthe imidoester with the acid chloride was carried out in excess pyridinewith mild heating. The intermediate (II) was usually thrown out ofsolution as an oil by addition of water, and hydrolyzed directly to theamide derivative (III). In the case of the N-acetyl derivatives, theacid anhydride was used in place of the chloride, and the intermediates(II) were readily isolated in a pure state.

The following example illustrates a developing solution which may beused with the compounds of our invention.

grams p-Amino-diethylaniline sulfate 2 Sodium sulfite (anhydrous) 5Sodium carbonate (anhydrous) 0 Potassium bromide 2 Water to 1 liter.

N-(Benzoylac'etyl) benz'amide grams..- 2 Sodium hydroxide (2% solution)cc 50 For use, B is added to A.

one or both sides of the support. The superposed layer may bedifferentially sensitized to record natural color photographic images inthe wellknown manner.

' The examples and compounds set forth in the present specification areillustrative only and it is to be understood that our invention islimited only by the scope of the appended claims.

We claim:

l. A color-forming photographic developer comprising a primary aromaticamino developing agent and a coupler compound having the formulaR-COCI-IsCONl-ICO-R where R is selected from the class consisting ofaryl and benzofuroyl radicals and R is selected from the classconsisting of alkyl and aryl radicals. 2. A color-forming photographicdeveloper comprising a primary aromatic amino developing agent and acoupler compound having the formula R-COCHzCONI-ICO-R' where R is anaryl radical and R is an aryl radical.

3. A color-forming photographic developer comprising a primary aromaticamino developing agent and a coupler compound having the formula where Ris a phenyl radical and R is a member of the group consistingof alkyland aryl radicals;

4. A color-forming photographic developer comprising a primary aromaticamino develop- 7 ing agent and N-(benzoylacetyl) benzamide.

5. A color-forming photographic developer comprising a primary aromaticamino developing agent and N-benzoyl-a-(4,5-benzofuroyl)acetamide. V

v6. The method'of producing a colored photographic image in a silverhalide emulsion layer which comprises exposing said layer and developing it with a primary aromatic amino developing agent in the presence ofa coupler compound having the formula V Rr-COCH2CONHCO-R a where R is anaryl radical and R is an aryl radical. I

8. The method of producing a color photoa graphic image in a silverhalide emulsion layer which comprises exposing said layer and developingit with a primary aromatic amino developing agent in the presence of acoupler compound hav- 7 ing the formula mooomoormco-H where R is aphenyl radical and R' is a member of the group consisting of alkyl andaryl radicals.

9. The method of producing a colored photographic image in a gelatinosilver halide emulsion layer which comprises exposing said layeranddeveloping it with a primary aromatic amino R-COCI-IzCONHCO-R' where R.is selected from the class consisting of aryl and benzoiuroyl radicalsand R is selected from the class consisting of alkyl and aryl radicals.

12. A photographic emulsion for forming colored images comprises agelatine silver halide emulsion having incorporated thereinN-[m-(ptert.-Amylphenoxy) benzoyl] -a- [p- (p-sec.- amyl- 5 phenyl)benzoyl] acetamide.

ARNOLD WEISSBERGER. HENRY D. PORTER.

REFERENCES 011mb The following references are of record in the file ofthis patent:

UNITED STATES PATENTS 15 Number Name a Date 2,366,324 Frohlich Jan. 2,1945 2,367,036 McQueen Jan. 9,1945

